Catheter with multi-functional control handle having rotational mechanism

ABSTRACT

A catheter for use in a patient&#39;s heart, especially for mapping a tubular region of the heart, has a catheter body, a deflectable intermediate section and a distal mapping assembly that has a generally circular portion adapted to sit on or in a tubular region of the heart. A control handle of the catheter allows for single-handed manipulation of various control mechanisms that can deflect the intermediate section and contract the mapping assembly by means of a deflection control assembly and a rotational control assembly. The deflection control assembly has a deflection arm and a rocker member. The rotational control assembly has an outer rotational member, an inner rotational member and a cam. A pair of puller members are responsive to the deflection control assembly to bi-directionally deflect the intermediate section. A third puller member is responsive to the rotational control assembly to contract the generally circular portion of the mapping assembly.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of and claims priority to and thebenefit of U.S. application Ser. No. 15/438,597 filed Feb. 21, 2017, nowU.S. Pat. No. 9,999,366, which is a continuation of and claims priorityto and the benefit of U.S. application Ser. No. 14/715,140 filed May 18,2015, now U.S. Pat. No. 9,572,958, which is a continuation of and claimspriority to and the benefit of U.S. application Ser. No. 12/550,307filed Aug. 28, 2009, now U.S. Pat. No. 9,033,916, the entire contents ofall of which are incorporated herein by reference.

FIELD OF INVENTION

This invention relates to a catheter, in particular, a catheter with acontrol handle having multiple control mechanisms for deflecting andcontracting portions of the catheter.

BACKGROUND

Electrode catheters have been in common use in medical practice for manyyears. They are used to stimulate and map electrical activity in theheart and to ablate sites of aberrant electrical activity. Atrialfibrillation is a common sustained cardiac arrhythmia and a major causeof stroke. This condition is perpetuated by reentrant waveletspropagating in an abnormal atrial-tissue substrate. Various approacheshave been developed to interrupt wavelets, including surgical orcatheter-mediated atriotomy. Prior to treating the condition, one has tofirst determine the location of the wavelets. Various techniques havebeen proposed for making such a determination, including the use ofcatheters with a mapping assembly that is adapted to measure activitywithin a pulmonary vein, coronary sinus or other tubular structure aboutthe inner circumference of the structure. One such mapping assembly hasa tubular structure comprising a generally circular main regiongenerally transverse and distal to the catheter body and having an outercircumference and a generally straight distal region distal to the mainregion. The tubular structure comprises a non-conductive cover over atleast the main region of the mapping assembly. A support member havingshape-memory is disposed within at least the main region of the mappingassembly. A plurality of electrode pairs, each comprising two ringelectrodes, are carried by the generally circular main region of themapping assembly.

In use, the electrode catheter is inserted into a guiding sheath whichhas been positioned a major vein or artery, e.g., femoral artery, andguided into a chamber of the heart. Within the chamber, the catheter isextended past a distal end of the guiding sheath to expose the mappingassembly. The catheter is maneuvered through movements that includedeflection of a distal portion of the catheter so that the mappingassembly is positioned at the tubular region in the heart chamber. Theability to control the exact position and orientation of the catheterand also the configuration of the mapping assembly is critical andlargely determines how useful the catheter is.

Steerable catheters are generally well-known. For example, U.S. Pat. No.Re 34,502 describes a catheter having a control handle comprising ahousing having a piston chamber at its distal end. A piston is mountedin the piston chamber and is afforded lengthwise movement. The proximalend of the elongated catheter body is attached to the piston. A pullerwire is attached to the housing and extends through the piston, throughthe catheter body, and into a tip section at the distal end of thecatheter body. The distal end of the puller wire is anchored in the tipsection of the catheter. In this arrangement, lengthwise movement of thepiston relative to the housing results in deflection of the catheter tipsection.

The design described in U.S. Pat. No. RE 34,502 is generally limited toa catheter having a single puller wire. If bi-directional deflection isdesire, more than one puller wire becomes necessary. Moreover, if morecontrol is desired, such as contraction of the mapping assembly, anadditional puller wire is needed. Space is limited within a controlhandle and operation of puller wire control mechanisms must notinterfere with components that extend through the control handle, suchas lead wires, cables, and irrigation tubing. Moreover, it is desirablethat the control mechanisms be arranged such that the catheter can beoperated single-handedly by the user. Accordingly, a need exists for acontrol handle capable of moving three puller wires for at least twoindependent movements, such as bi-directional deflection of the cathetershaft and contraction of the mapping assembly, preferably through asingle-handed manipulation of the user.

SUMMARY OF THE INVENTION

The present invention is directed to a catheter for use in a patient'sheart, especially for mapping a tubular region of the heart. In oneembodiment, the catheter has a catheter body and a deflectableintermediate section distal the catheter body. Distal the intermediatesection is a mapping assembly that has a generally circular portionadapted to sit on or in a tubular region of the heart. A control handleof the catheter allows for single-handed manipulation of various controlmechanisms that can deflect the intermediate section and contract themapping assembly by means of a deflection control assembly and arotational control assembly. The deflection control assembly has adeflection arm and a rocker member. The rotational control assembly hasan outer rotational member, an inner rotational member and a cam. A pairof puller members are responsive to the deflection control assembly tobi-directionally deflect the intermediate section. A third puller memberis responsive to the rotational control assembly to contract thegenerally circular portion of the mapping assembly.

In a more detailed embodiment, a proximal end of the third puller memberis anchored in the rotational control assembly, such that rotation ofthe outer rotational member by a user moves the third puller memberlongitudinally relative to the catheter body. The outer rotationalmember generally surrounds the inner rotational member and the innerrotational member is rotatably mounted on the cam. The control assemblyincludes a follower to which a proximal end of the third puller memberis anchored and the follower is adapted to follow the movement of theinner rotational member so as to slide in a track formed on the cam. Ina more detailed embodiment, the track is helical on the cam, and theouter and inner rotational members are rotationally coupled byformations, that include interlocking teeth or fingers that engageholes.

The rotational control assembly can be arranged such that the innerrotational member and the outer rotational member have a commonrotational axis, or different rotational axes. Moreover, the rotationalcontrol assembly can be located either proximally or distally of thedeflection control assembly. The control handle can include a tensioncontrol assembly adapted to adjust tension of the deflection controlassembly.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reference to the following detailed descriptionwhen considered in conjunction with the accompanying drawings. It isunderstood that selected structures and features have not been shown incertain drawings so as to provide better viewing of the remainingstructures and features.

FIG. 1 is a top plan view of one embodiment of the catheter of thepresent invention.

FIG. 2A is a side cross-sectional view of an embodiment of a junction ofa catheter body and an intermediate section, taken along a firstdiameter.

FIG. 2B is a side cross-sectional view of the embodiment of the junctionof FIG. 2a , taken along a second diameter generally perpendicular tothe first diameter.

FIG. 3 is a side view of a distal portion of the catheter of FIG. 1,including an intermediate section and a mapping assembly.

FIG. 4 is a longitudinal cross-sectional view of the intermediatesection of FIG. 3, taken along line 4-4.

FIG. 5 is a schematic view of the mapping assembly showing onearrangement of the ring electrodes.

FIG. 6 is a longitudinal cross-sectional view of the mapping assembly ofFIG. 3 along line 6-6.

FIG. 7 is a side cross-sectional view of an embodiment of a distal endof the mapping assembly of FIG. 3.

FIG. 8a is a side cross-sectional view of an embodiment of a junctionbetween the intermediate section and the mapping assembly, taken along afirst diameter.

FIG. 8b is a side cross-sectional view of an embodiment of a junctionbetween the intermediate section and the mapping assembly, taken along asecond diameter generally perpendicular to the first diameter.

FIG. 9 is a top plan view of an embodiment of a control handle housinghalf including an embodiment of a deflection control assembly.

FIG. 10 is a top perspective view of an embodiment of a rocker member ofa deflection control assembly.

FIG. 11 is a bottom perspective view of an embodiment of a rockermember.

FIG. 12 is a side view of an embodiment of a pulley of a deflectioncontrol assembly.

FIG. 13a-13c are schematics of an embodiment of the deflection controlassembly in neutral and rotated configurations.

FIG. 14 is a longitudinal cross section of an embodiment of thedeflection control assembly and tension control assembly mounted on acontrol handle.

FIG. 14a is a detailed view of a portion of FIG. 14, including anembodiment of a retaining nut and a tension screw.

FIG. 15 is a partial perspective view of an embodiment of a firstcontrol handle housing half.

FIG. 16 is a perspective view of an embodiment of a deflection arm.

FIG. 17 is a perspective view of an embodiment of a tension controldial.

FIG. 18 is a perspective view of an embodiment of a locking plate.

FIG. 19 is a partial perspective view of a portion of an embodiment of acontrol handle.

FIG. 20 is a partial perspective view of a portion of an embodiment of adeflection arm and a tension control member mounted on a control handle.

FIG. 21 is a partial perspective view of a portion of an embodiment of asecond control handle housing half and a retaining nut, the secondcontrol housing half adapted to oppose the first control handle housinghalf.

FIG. 22 is a perspective view of the tension control dial of FIG. 17 andlocking plate of FIG. 18 as assembled.

FIG. 23 is an exploded perspective view of an embodiment of a rotationalcontrol assembly.

FIG. 24 is a side cross-sectional view of the rotational controlassembly of FIG. 23, as assembled on a control handle.

FIG. 25 is a longitudinal cross-sectional view of the rotational controlassembly of FIG. 24, taken along line b-b.

FIG. 26 is a longitudinal cross-sectional view of the rotational controlassembly of FIG. 24, taken along line a-a.

FIG. 27 is an exploded perspective view of an alternate embodiment of arotational control assembly.

FIG. 28 is a side cross-sectional view of the rotational controlassembly of FIG. 27, as assembled on a control handle.

FIG. 29 is a longitudinal cross-sectional view of the rotational controlassembly of FIG. 27, taken along line a-a.

FIG. 30 is a longitudinal cross-sectional view of the rotational controlassembly of FIG. 27, taken along line b-b.

FIG. 31 is a longitudinal cross-sectional view of the rotational controlassembly of FIG. 27, taken along line c-c.

FIG. 32 is a partial perspective view of an alternate embodiment of acontrol handle housing half.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the present invention is directed to a catheter 10with multiple control capabilities for mapping and/or ablation of theheart. In the illustrated embodiment of FIG. 1, a catheter 10 comprisesan elongated catheter body 12, a deflectable intermediate section 14 ata distal end of the catheter body 12, a tip section 15 including amapping assembly 17 at a distal end of the intermediate section 14, anda multi-functional control handle 16 at a proximal end of the catheterbody 12 for controlling portions of the catheter, for example,deflecting the intermediate section 14 and contracting the mappingassembly 17.

With reference to FIGS. 2A and 2B, the catheter body 12 comprises asingle, central or axial lumen 18. The catheter body 12 is flexible,i.e., bendable, but substantially non-compressible along its length. Thecatheter body 12 may be of any suitable construction and made of anysuitable material. A suitable construction comprises an outer wall 22made of a polyurethane or nylon. The outer wall 22 comprises an imbeddedbraided mesh of stainless steel or the like to increase torsionalstiffness of the catheter body 12 so that, when the control handle 16 isrotated, the tip section of the catheter 10 will rotate in acorresponding manner.

The outer diameter of the catheter body 12 is not critical, but ispreferably no more than about 8 French. Likewise the thickness of theouter wall 22 is not critical. The inner surface of the outer wall 22 islined with a stiffening tube 20, which can be made of any suitablematerial, e.g., polyimide. The stiffening tube 20 is held in placerelative to the outer wall 22 at the proximal end of the catheter body12. A first glue joint 23 is made between the distal ends of thestiffening tube 20 and the outer wall 22 by a fast drying glue, e.g.Super Glue®. Thereafter a second glue joint 25 is formed between theproximal ends of the stiffening tube 20 and outer wall 22 using a slowerdrying but stronger glue, e.g., polyurethane.

The stiffening tube, along with the braided outer wall 22, providesimproved torsional stability while at the same time minimizing the wallthickness of the catheter, thus maximizing the diameter of the singlelumen. The outer diameter of the stiffening tube 20 is about the same asor slightly smaller than the inner diameter of the outer wall 22.Polyimide tubing is suitable because it may be very thin walled whilestill providing very good stiffness. This maximizes the diameter of thecentral lumen 18 without sacrificing strength and stiffness. Polyimidematerial is typically not used for stiffening tubes because of itstendency to kink when bent. However, it has been found that, incombination with an outer wall 22 of polyurethane, nylon or othersimilar material, particularly having a stainless steel braided mesh,the tendency for the polyimide stiffening tube 20 to kink when bent isessentially eliminated with respect to the applications for which thecatheter is used.

In one embodiment, the outer wall 22 has an outer diameter of about0.092 inch and an inner diameter of about 0.063 inch and the polyimidestiffening tube 20 has an outer diameter of about 0.0615 inch and aninner diameter of about 0.052 inch.

As shown in FIGS. 2A, 2B and 4, the intermediate section 14 comprises ashorter section of tubing 19 with multiple off-axis lumens, for example,first, second, third and fourth lumens 30, 31, 32 and 33. The tubing 19is made of a suitable non-toxic material which is preferably moreflexible than the catheter body 12. A suitable material for the tubing19 is braided polyurethane, i.e., polyurethane with an embedded mesh ofbraided stainless steel or the like. The outer diameter of theintermediate section 14, like that of the catheter body 12, ispreferably no greater than about 8 French. The size of the lumens is notcritical. In one embodiment, the intermediate section has an outerdiameter of about 7 French (0.092 inch) and the lumens are generallyabout the same size, having a diameter of about 0.022 inch, or selectedlumens can have a slightly larger diameter of about 0.036 inch.

A means for attaching the catheter body 12 to the intermediate section14 is illustrated in FIGS. 2A and 2B. The proximal end of theintermediate section 14 comprises an inner counter bore 24 that receivesthe outer surface of the polyimide stiffener 20. The intermediatesection 14 and catheter body 12 are attached by glue 29 or the like.

As shown in FIGS. 2A and 2B, extending through the single lumen 18 ofthe catheter body 12 are various components, for example, lead wires andmultiple puller members, and any other wires or cables. Longitudinalmovement of the puller members relative to the catheter body 12 enableuser control of various parts of the catheter via the control handle. Inone embodiment, the puller members include a pair of deflection pullermembers 42 for deflecting the intermediate section 14 and a contractionpuller member 35 for adjusting the mapping assembly 17 of the tipsection 15.

A single lumen catheter body 12 can be preferred over a multi-lumen bodybecause the single lumen 18 body can permit better tip control whenrotating the catheter 10. The single lumen 18 permits the componentspassing therethrough to float freely within the catheter body. If suchcomponents were restricted within multiple lumens, they can build upenergy when the handle 16 is rotated, resulting in the catheter body 12having a tendency to rotate back if, for example, the handle isreleased, or if bent around a curve, to flip over, either for which areundesirable performance characteristics.

A deflection puller member 42 extends through the central lumen 18 ofthe catheter body 12 and into the second lumen 31 of the intermediatesection 14. Another deflection puller member 42 extends through thecentral lumen 18 and into the fourth lumen 33 of the intermediatesection 14. The distal ends of the deflection puller members 42 areanchored to the wall of the tubing 19 near the distal end of theintermediate section 14 by means of T-anchors 83 (FIG. 8b ). In theintermediate section 14, each deflection puller members 42 extendsthrough a plastic, e.g., Teflon®, sheath 81, which prevents thedeflection puller members 42 from cutting into the wall of the tubing 19of the intermediate section 14 when the intermediate section 14 isdeflected.

As shown in FIG. 2B, compression coils 44 in surrounding relation to thedeflection puller members 42 extend from the proximal end of thecatheter body 12 to the proximal end of the intermediate section 14. Thecompression coils 44 are made of any suitable metal, e.g., stainlesssteel. The compression coils 44 are tightly wound on itself to provideflexibility, i.e., bending, but to resist compression. The innerdiameter of the compression coils 44 is preferably slightly larger thanthe diameter of the puller wires 42. For example, when a puller member42 has a diameter of about 0.007 inches, the compression coil 44preferably has an inner diameter of about 0.008 inches. The Teflon®coating on the puller member 42 allows them to slide freely within thecompression coils 44. The outer surface of the compression coils 44 iscovered by a flexible, non-conductive sheath 27 to prevent contactbetween the compression coils 44 and other components, such as leadwires and cables, etc. A non-conductive sheath can be made of polyimidetubing.

The compression coils 44 are anchored at their proximal ends to theproximal end of the stiffening tube 20 in the catheter body 12 by gluejoint 50 (FIG. 2B) and at its distal end near the proximal end of theintermediate section 14 in the second lumen 31 and fourth lumen 33 byglue joints 49 (FIG. 2B).

With reference to FIG. 3, at the distal end of the intermediate shaft 14is the mapping assembly 17. The mapping assembly 17 comprises agenerally straight proximal region 38 and a generally circular mainregion 39. The proximal region 38 is mounted on the intermediate section14, as described in more detail below, so that it is generally a linearextension of the intermediate section 14. In one embodiment, theproximal region 38 has an exposed length, e.g., not contained within theintermediate section 14, ranging from about 3 mm to about 12 mm, morepreferably about 3 mm to about 8 mm, still more preferably about 5 mm,but can vary as desired.

The generally circular main region 39 is generally traverse, if not alsoperpendicular, to the catheter body 12. The generally circular mainregion 39 can form a flat circle or can be very slightly helical. In oneembodiment, the main region 39 has an outer diameter ranging from about10 mm to about 25 mm, more preferably about 12 mm to about 20 mm. Thegenerally circular main region 39 can curve in a clockwise direction ora counterclockwise direction. As shown in FIGS. 5, 6 and 7, the mappingassembly 17 is formed of a non-conductive cover or tubing 52 which canhave any cross-sectional shape as desired. The non-conductive cover 52can be made of any suitable material, and is preferably made of abiocompatible plastic such as polyurethane or PEBAX. The non-conductivecover 52 can be pre-formed into the desired generally circular shape ofthe generally circular main region 39. Alternatively, the shape of thegenerally circular main region 39 can be defined by a wire or othercomponent extending through the non-conductive cover 52.

In the depicted embodiment, a pre-formed support member 54 extendsthrough the non-conductive cover 52 to define the shape of the generallycircular main region 39. The support member 54 is made of a materialhaving shape-memory, i.e., that can be straightened or bent out of itsoriginal shape upon exertion of a force and is capable of substantiallyreturning to its original shape upon removal of the force. On suitablematerial for the support member 54 is a nickel/titanium alloy. Suchalloys typically comprise about 55% nickel and 45% titanium, but maycomprise from about 54% to about 57% nickel with the balance beingtitanium. A suitable nickel/titanium alloy is Nitinol, which hasexcellent shape memory, together with ductility, strength, corrosionresistance, electrical resistivity and temperature stability.

A series of ring electrodes 26 are mounted on the non-conductive cover52 of the generally circular main region 39 of the mapping assembly 17,as shown in FIG. 5. The ring electrodes 26 can be made of any suitablesolid conductive material, such as platinum or gold, or a combination ofplatinum and iridium, and mounted onto the non-conductive cover 52 withglue or the like. Alternatively, the ring electrodes 26 can be formed bycoating the non-conductive cover 52 with an electrically conductingmaterial, like platinum, gold and/or iridium. The coating can be appliedusing sputtering, ion beam deposition or an equivalent technique. Asuitable mapping assembly is described in U.S. Pat. No. 7,274,957, theentire disclosure of which is hereby incorporated by reference. Ifdesired, additional electrodes (not shown) could be mounted along theintermediate section 14 and/or the generally straight proximal section38.

The contraction puller member 35, for example, a contraction pullerwire, is provided to contract the generally circular main region 39 tothereby change or reduce its diameter, for example, when mapping orablating circular or tubular regions of the heart. The contraction wire35 has a proximal end anchored in the control handle 16, which is usedto manipulate the contraction wire as described further below. Thecontraction wire 35 extends through the central lumen 18 of the catheterbody 12, through the third lumen 32 of the intermediate section 14 andinto the non-conductive cover 52 of the mapping assembly 17. The portionof the contraction wire 35 extending through the non-conductive cover 52is positioned on the side of the generally circular main region 39closer to the center of the generally circular main region, as bestshown in FIG. 6. The center of the generally circular main region refersto the center of the circle formed by the generally circular mainregion. With this arrangement, contraction of the generally circularmain region 39 is dramatically improved over arrangements where theposition of the contraction wire 35 is not so controlled.

As shown in FIGS. 5 and 6, within the mapping assembly 17, thecontraction wire 35 extends through a plastic tube 55. In oneembodiment, the plastic tube 55 comprise three layers, including aninner layer of polyimide over which a braided layer is formed, thebraided layer comprising a braided stainless steel mesh or the like, asis generally known in the art. The braided layer enhances the strengthof the plastic tube 55, reducing the tendency for contraction wire 35 tostraighten the preformed curve of the mapping assembly 17. A thinplastic layer of polytetrafluoroethylene is provided over the braidedlayer to protect the braided layer from getting tangled with the leadwires 40 within the non-conductive cover 52. The plastic tube 55 has aproximal end anchored to the distal end of the intermediate section 14in the third lumen 32 by glue or the like (FIG. 8a ). The support member54 extends through the plastic tube 55 with the contraction wire 35(FIG. 8a ). The distal ends of the support member 54 and the contractionwire 35 are soldered or otherwise attached to a small stainless steeltube 53 (FIG. 7). With this arrangement, the relative positions of thecontraction wire 35 and the support member 54 can be controlled so thatthe contraction wire can be positioned on the side of the generallycircular region 39 closer to the center of the generally circular region39, as described above. The contraction wire 35 on the inside of thecurve pulls the support member 54 to the inside of the curve, enhancingcontraction of the generally circular region 39. Further, when theplastic tube 55 includes a braided layer, it keeps the contraction wire35 from tearing through the non-conductive cover 52.

A third compression coil 46 is situated within the catheter body 12 andintermediate section shaft 14 in surrounding relation to the contractionwire 35 (FIG. 2A). The third compression coil 46 extends from theproximal end of the catheter body 12 to near the distal end of the thirdlumen 32 of the intermediate section 14. The third compression coil 46is made of any suitable metal, e.g., stainless steel, and is tightlywound on itself to provide flexibility, i.e., bending, but to resistcompression. The inner diameter of the third compression coil 46 ispreferably slightly larger than the diameter of the contraction wire 35.The outer surface of the compression coil 46 is covered by a flexible,non-conductive sheath 68, e.g., made of polyimide tubing. The thirdcompression coil 46 can be formed of a wire having a square orrectangular cross-sectional area, which makes it less compressible thana compression coil formed from a wire having a circular cross-sectionalarea. As a result, the third compression coil 46 keeps the catheter body12, and particularly the intermediate section 14, from deflecting whenthe contraction wire 35 is manipulated to contract the mapping assembly17 as it absorbs more of the compression.

The third compression coil 46 is anchored at its proximal end to theouter wall 20 of the catheter body 12 by the proximal glue joint 50 andto the intermediate section 14 by distal glue joint 72.

It is understood that glue joints throughout the catheter 10 maycomprise polyurethane glue or the like. The glue may be applied by meansof a syringe or the like through a hole made in the tubing walls. Such ahole may be formed, for example, by a needle or the like that puncturesthe tubing walls where the needle is heated sufficiently to form apermanent hole. The glue is then introduced through the hole to wickaround the component(s) within the tubing to form a glue joint about theentire circumference of the component(s).

In the depicted embodiment of FIG. 7, the distal end of the mappingassembly 17 is sealed closed with a dome 51 of polyurethane glue or thelike. A short ring 56, made of metal or plastic, and e.g., polyamide, ismounted within the distal end of the non-conductive cover 52. The shortring 56 prevents the distal end of the non-conductive cover 52 fromcollapsing, there by maintaining the diameter of the non-conductivecover at its distal end.

At the junction of the intermediate section 14 and the mapping assembly17 as shown in FIGS. 8a and 8b , the non-conductive cover 52 is attachedto the intermediate section 14 by glue or the like. The plastic tube 55has its proximal end inserted and glued in the distal end of theintermediate section 14. The glue (not shown) from the plastic tube 55can further serve to anchor the distal end of the third compression coil46 in place within the third lumen 32. The support member 54 extendsfrom the third lumen 32 into the plastic tube 55 within thenon-conductive cover 52. The proximal end of the support member 54terminates a short distance proximally from the distal end of the thirdlumen 32, approximately about 5 mm, so as not to adversely affect theability of the intermediate section 14 to deflect. However, if desired,the proximal end of the support member 54 can extend proximally furtherinto the intermediate section 14 and/or the catheter body 12.

The lead wires 40 attached to the ring electrodes 26 extend through thefirst lumen 30 of the intermediate section 14 (FIG. 2A), through thecentral lumen 18 of the catheter body 12, through the control handle 16,and terminate at their proximal end in a connector (not shown) which isconnected to an appropriate monitor or other device for receiving anddisplaying the information received from the ring electrodes 26. Theportion of the lead wires 40 extending through the central lumen 18 ofthe catheter body 12, control handle 16 and proximal end of theintermediate section 14 is enclosed within a protective sheath 62, whichcan be made of any suitable material, such as polyimide. The protectivesheath 62 is anchored at its distal end to the proximal end of theintermediate section 14 by gluing it in the lead wire lumen 30 withpolyurethane glue or the like to form glue joint 73.

The lead wires 40 are attached to the ring electrode 26 by anyconventional technique. In one embodiment, each ring electrode 26 ismounted by first forming a hole in the non-conductive cover 52. Anelectrode lead wire 40 is fed through the hole, and the ring electrode26 is welded in place over the lead wire and non-conductive cover 52.

With reference to FIG. 1, the control handle 16 comprises a generallyelongated handle housing, which can be made of any suitable rigidmaterial, such as plastic configured through a suitable molding process.In the illustrated embodiment, the housing includes two opposing halves16 a and 16 b that generally mirror each other and are joined by glue,sonic welding or other suitable means along a longitudinal peripheralseam 28 around the housing. In the illustrated embodiment, the crosssection of the handle 16 formed by the opposing halves changes along thelength of the handle. A more distal portion 112 has a smaller, generallyrectangular cross section. A mid-portion 114 has a larger, generallyrectangular cross section. A more proximal portion 116 has a generallycircular cross section.

In the illustrated embodiment of FIGS. 1 and 9, the control handle 16houses components of a deflection control assembly 74 in the mid-portion114. The deflection control assembly includes a deflection member or arm75 that can be directly manipulated by an operator to control deflectionof the intermediate section 14. The deflection arm 75 is rotatable aboutan axis 76 that is generally transverse or perpendicular to thelongitudinal axis of the control handle. The deflection control assembly74 has a rotatable rocker member 78 that acts on the deflection pullermembers 42 to deflect the intermediate section 14.

The rocker member 78 has a length L dimension, a width W dimension and athickness T dimension (FIGS. 10 and 11). Along its thickness dimensionT, the rocker member 78 is configured with two opposing annularformations 140 a and 140 b that define a central hole or passage 143that extends through its entire thickness. The central hole 143 isaligned with the rotational axis 76 of the deflection arm 75. Along itslength dimension L, the rocker member 78 also has two smaller holes 146that oppose each other across the central hole 143. In each hole sits apulley 147, for example, a snap bearing (FIG. 12), that has a rotationalaxis parallel to the axis 76. Each deflection puller member 42 entersthe rocker member through slots 148 and a portion is wound around arespective pulley 147.

As understood by one of ordinary skill in the art, the rocker member 78and the pulleys 147 are arranged such that rotation of the rocker memberin one direction about the axis 76 draws back one puller member 42 todeflect the intermediate section 14 in that direction. With reference toFIGS. 13a-13c , as the rocker member 78 is rotated by means of thedeflection arm (as represented by line 75), the pulleys 147 aredisplaced from a neutral position (FIG. 13a ) with one pulley 147drawing a puller member 42 on one side of the catheter body 12 againstits anchored proximal end for deflecting the intermediate section 14toward that side (FIGS. 13b and 13c ).

Each deflection puller member 42 may comprise multiple segments. Asillustrated in FIG. 9, each deflection puller member has a distal pullerwire 42 a and a proximal fiber 42 b that are joined or connected at alocation within the control handle 16 distal the rocker member 78. Thepuller wire 42 a and the tensile fiber 42 b of each deflection pullermember are connected or secured to each other by a connector 154, e.g.,a crimped brass ferrule covered by shrink tubing. Each puller wire 42 aextends through the catheter body 12 and the intermediate section 14.Each tensile fiber 42 b extends inside the control handle 16. In thismanner, it is the more flexible tensile fibers 42 b that interact withthe pulleys 147 and undergo repeated bending and straightening duringdeflection operations, as they are less prone to bending stress andfatigue failure.

Each puller wire 42 a is made of any suitable metal, such as stainlesssteel or Nitinol. Preferably each puller wire has a low frictioncoating, such as a coating of Teflon® or the like. Each puller wire hasa diameter preferably ranging from about 0.006 inch to about 0.012 inch.Preferably both of the puller wires have the same diameter. Flat pullerwires may be used in place of round puller wires. Their cross sectionaldimensions should be such that they provide comparable tensile strengthsas round puller wires.

Each tensile fiber 42 b may be of a high modulus fiber material,preferably having an ultimate tensile strength substantially in therange of 412-463 ksi (2480-3200 Mpa) such as High Molecular DensityPolyethylene (e.g., Spectra™ or Dyneema™), a spun para-aramid fiberpolymer (e.g., Kevlar™) or a melt spun liquid crystal polymer fiber rope(e.g., Vectran™), or a high strength ceramic fiber (e.g., Nextel™). Theterm fiber is used herein interchangeably with the term fibers in thatthe tensile fiber may be of a woven or braided construction. In anycase, these materials tend to be flexible, providing suitable durabilitywhen used in wrapped engagement with the pulleys and the like forgreater throw in deflecting the catheter tip. Further, they aresubstantially non-stretching, which increases the responsiveness to themanipulation of the control handle, and nonmagnetic so that theygenerally appear transparent to an MRI. The low density of the materialcauses it to be generally transparent to an x-ray machine. The materialscan also be nonconductive to avoid shorting. Vectran™ for example, hashigh strength, high abrasion resistance, is an electrical insulator,nonmagnetic, is polymeric, and has low elongation under sustainedloading conditions.

In the illustrated embodiment of FIG. 9, each tensile fiber 42 b extendsproximally from the connector 154 toward the rocker member 78 where eachis wound around a respective pulley 147 and turns about 180 degrees todouble back toward the distal end of the control handle. Each proximalend of the tensile fiber 42 b is anchored by an anchor assembly 90 thatincludes a pair or racks 92, a slug 94 and a stop 96. The proximal endof each tensile fiber 22 b extends between a channel 91 defined by thepair of racks 92, and the proximal end of each tensile fiber is encasedwithin a molded member or slug 94 sized to fit in and translate in thechannel 91. Proximal the slug are the stops 96 that are adjustablypositioned in a selected location along the racks 92, for example, bymeans of interlocking teeth 98 formed in the racks and the stops toreleasably lock in the selected position against movement. The stops 96are formed so that each respective tensile fiber 42 b can slide throughor below them while blocking the slugs 94 from moving proximally pastthem. Accordingly, the stops 96 limit the proximal movement of the slugs94 and anchor the proximal ends of the tensile fibers 42 b to effectuatedeflection when each is drawn proximally by the deflection controlassembly 74. During assembly of the control handle 16, before the twohousing halves 16 a, 16 b are joined, the stops 96 are selectivelypositioned between the racks 92 to achieve a desirable tension in eachtensile member. The interlocking teeth 98 of the racks 92 and stops 96allow for fine adjustments in setting the tension.

The construction and assembly of the deflection control assembly 74including the deflection arm 75 and a tension adjustment member 101 onthe control handle 16 are described as follows. With reference to FIGS.14 and 14 a, the rocker member 78 of the assembly 74 is situated betweenthe two halves 16 a and 16 b of the control handle 16, with each of itsannular formations 140 a and 140 b extending respectively through anopening 120 a, 120 b formed in the distal portion 114 of each housinghalf 16 a and 16 b.

The annular formation 140 a has recesses 160 (FIG. 10) exposed throughthe opening 120 a (FIG. 15) that receive protrusions 152 projecting froma facing surface 154 of the deflection arm 75 (FIG. 16) to rotationallycouple the deflection arm 75 and the rocker member 78. The protrusions152 can snap fit into the recesses 160 and/or be secured by adhesives,glue, sonic welding and the like. A central circular protrusion 156 fromthe deflection arm 75 fits into the hole 143 circumscribed by theannular formation 140 a of the rocker member 78. A suitable deflectionassembly and control handle are described in co-pending U.S. applicationSer. No. 12/346,834, filed Dec. 30, 2008 (U.S. 2010/0168827 A1), theentire disclosure of which is hereby incorporated by reference. Anothersuitable deflection assembly with deflection sensitivity is described inco-pending U.S. application Ser. No. 12/211,728, filed Sep. 16, 2008(U.S. US 2010-0069834 A1), the entire disclosure of which is herebyincorporated by reference. Therein, a cam that is responsive to adeflection sensitivity knob can vary the separation distance between thetwo pulleys 147, thereby changing the deflection sensitivity of thedeflection arm.

Opposing the deflection arm 75 is the deflection tension adjustmentmember or dial 101 (FIGS. 17 and 20) which is coupled to and indirectlyengaged with the rocker member 78 by various mechanisms and parts andallows an operator to adjust the ease with which the deflection arm 75can be rotated. Mounted primarily on the housing half 16 b, theillustrated embodiment of a tension adjustment assembly 100 includes theadjustment dial 101 (FIG. 17), a locking plate 102 (FIG. 18), a tensioncap screw 103, a retaining nut 136 and a washer 119 (see FIGS. 14 and 14a). A user rotates the dial 101 to adjust the tightness or tension ofthe rotational movement of deflection arm 75 by effectively compressingor releasing the rocker member 78 against the washer 119 (e.g., aBelleville type) and the control handle housing half 16 b.

The dial 101 has a generally circular cross section with acircumferential edge 115 having a friction-inducing surface (FIG. 17). Acentral circular protrusion 105 and a plurality of prongs 106 (FIG. 17)situated along a diameter of the dial project from a surface 104 of thedial 101.

The locking plate 102 is sandwiched between the dial 101 and the handlehousing 16 b (FIG. 20). The locking plate 102 (FIG. 18) has a centrallarger hole 107 and two smaller holes 108, all three of which extendthrough the entire thickness of the locking plate. The two prongs 106 ofthe dial 101 are adapted to be inserted through the smaller holes 108 inthe plate 102 (FIG. 21) and received in semi-circular grooves 109 (FIG.19) formed in an outer surface of the housing half 16 b. The grooves 109limit the degree of rotation of the dial 101 in clockwise andcounterclockwise directions. The central hole 107 of the plate 102 (FIG.18) has different cross-sections that include a larger circularcross-section 107 a and a smaller circular cross-section 107 b. Thelarger circular cross-section 107 a receives a head 112 of a cap screw103, and the smaller circular cross-section 107 b receives a threadedbody 114 of the cap screw 103 (FIG. 14a ).

The threaded body 114 of the cap screw 103 extending through the centralhole 107 of the locking plate 102 engages the retaining nut 136 situatedin the opening 143 of the rocker member 78. A head 115 of the nut abutsand is anchored against a neck 132 formed in the inner surface of theopening 143 of the rocker member 78. The opening 120 b in the housinghalf 16 b (FIG. 21) has a larger cross section 122 and a smaller crosssection 124. The smaller cross section 124 has a polygonal shape whichmatches a polygonal (e.g., hexagonal) end 126 of the nut 136 so that thenut 136 is effectively locked against rotation relative to the housinghandle 16 b.

The central protrusion 105 of the dial 101 (FIG. 17) forms a press orinterference fit with the head 112 of the cap screw 103 to createrotational alignment between these two components. The prongs 106 of thedial 101 lock and rotationally couple the dial 101 and the lock plate102, and the cap screw 103 is rotationally coupled to the locking plate102. Coupling of the dial 101 and the locking plate 102 may also beachieved by means of welding the two components together. In that case,the prongs 106 need not protrude from the dial 101 but can insteadextend from the locking plate 102.

Between the polygonal end 126 of the nut 136 and the housing handle 16 bis the washer 119 whose compression against the nut 136 and the housinghandle 16 b is adjustable by the user's rotation of the dial 101 whichtightens or releases the engagement between cap screw 103 and the nut136, thus increasing or decreasing the ease with which the rocker member78 and hence the deflection arm 75 can be rotated.

Components that extend through the control handle, including, forexample, the lead wires 40 and the contraction wire 35 also enter thecontrol handle at the distal end. In the illustrated embodiment of FIG.9, these components extend along the longitudinal axis of the controlhandle. A protective tubing 152 through which the components extend canbe provided, positioned between the two deflection puller members 42 andthrough a channel 150 form through the width dimension W of the rockermember 78 (FIG. 11). Distal and proximal portions of the channel 150have indents, e.g., triangular or wedge-shaped, 151 (FIGS. 9 and 11) toallow the rocker member 78 to rotate freely within a predetermined rangeof angles, e.g., about ±45 degrees of the longitudinal axis of thecontrol handle 16, without interference by the tubing 152 and thecomponents therethrough.

Alternatively, the components extending through the control handle, withthe exception of the contraction wire 35, are routed on an off-axis path153 diverging from the deflection puller members 42 at entry into thedistal end of the control handle 16. The components thus extend alongthe periphery of the housing handle, bypassing the rocker member 78.

It is understood that the distance between the distal end of thecompression coils 44 and the distal anchor sites of each deflectionpuller members 42 in the intermediate section 14 determines thecurvature of the intermediate section 14 in the direction of thedeflection puller members. For example, an arrangement wherein the twodeflection puller members 42 are anchored at different distances fromthe distal ends of the compression coils 44 allows a long reach curve ina first plane and a short reach curve in a plane 90.degree. from thefirst, i.e., a first curve in one plane generally along the axis of theintermediate section 14 before it is deflected and a second curve distalto the first curve in a plane transverse, and preferably normal to thefirst plane. The high torque characteristic of the catheter intermediatesection 14 reduces the tendency for the deflection in one direction todeform the deflection in the other direction. Suitable deflectioncontrol handles and parts thereof for use with such a catheter aredescribed in U.S. Pat. No. 6,123,699, U.S. Pat. No. 6,171,277, and U.S.Pat. No. 6,183,463, the entire disclosures of which are herebyincorporated by reference.

For adjusting the mapping assembly 17 by means of a third puller member,e.g., the contraction wire 35, a distal end of the contraction wireextending between the two deflection puller members 42 within thecontrol handle is anchored in the control handle for actuation by meansof a rotational control assembly 200. In the illustrated embodiment ofFIG. 23, the rotational control assembly 200 includes an outerrotational member (or control knob) 202, a cam 206 whose body 207supports an inner rotational member (or gear) 204, the combination ofwhich effectuates longitudinal movement of the contraction wire 35relative to the catheter body 12, for example, to contract and expandthe mapping assembly 17. With reference to FIGS. 23-25, the proximalportion 116 of the control handle 16 on which the rotational controlassembly is mounted has a generally circular cross section of an innerdiameter D1 and an outer diameter D2. In the disclosed embodiment, therotational control assembly 200 is positioned proximal the deflectioncontrol assembly 74, although it is understood that it can be positioneddistal the deflection control assembly 74.

In the disclosed embodiment, the outer rotational control knob 202 ismounted on the proximal portion 116 of the control handle. The knob 202formed from two halves 202 a, 202 b adapted for snap-fit or joined byglue or sonic welding to each other is received in an outercircumferential recess 208 (see also FIG. 15) formed in the outersurface of control handle 16. The outer control knob 202 when assembledfrom the halves 202 a, 202 b is generally cylindrical, for example, inthe shape of a ring, with an inner diameter D3 that is slightly greaterthan the recess 208 so that the knob 202 can be rotated around thecontrol handle 16 within the recess 208. There can be circumferentialcontact between the knob 202 and the control handle 16 so long as theknob can be rotated in the recess 208. So mounted on the control handle,the knob is concentric with the proximal portion 116 of the controlhandle so that rotation of the knob is on axis with the longitudinalaxis of the control handle. An outer surface of the knob hasfriction-inducing formations 210 to facilitate rotation of the knob 202by a user of the catheter. A portion of the knob may have a diameter D4that is greater than the outer diameter D2 of the handle.

The cam 206 on which the gear 204 is supported has a cylindrical body207, and a collar 209 at a distal end. The gear 204 is mounted on thecylindrical body 207 of the cam so that the longitudinal axis of the cam206 defines the rotational axis of the gear 204. The gear rotates on andabout the cam 206. A portion of the collar 209 (e.g., a bottom portionin FIG. 23) is received in and affixed to a recess 230 (FIG. 15) formedin the inner surface of the control handle housing at a location X. Theaffixation of the collar 209 secures the cam 206 to the handle 16, andhence fixes the rotational axis of the gear 204 within and relative tothe handle 16.

For rotationally coupling the knob 202 and the gear 204, for example,engaging and imparting rotational movement from the knob to the gear,inner surface of the knob 202 and outer surface of the gear 204 haveformations such as interlocking teeth 212 and 214 (FIG. 24). In theillustrated embodiment, outer diameter D5 of the gear 204 issignificantly smaller than the diameter D1 of the cross section of thehandle 16 and the diameters D3 and D4 of the control knob 202, forexample, by 50% or more, such that the axis of rotation of the gear 204is off axis from the rotational axis of the knob 202 and thelongitudinal axis of the control handle. Thus, only a portion of theteeth 212 and 214 engage each other at any one time.

The engagement between the teeth occurs through an opening or hole 220(FIG. 24) formed in the handle 16 by the joinder of radial cutouts 222(FIG. 15) in the two control handle housing halves 16 a and 16 b. It isunderstood that the opening 220 is not limited to the locationillustrated but can be at any location around the circumference of thehandle 16. The opening 220 in the handle 16 through which the teeth 212,214 of the gear 204 and the outer ring 202 intermesh is immediatelyadjacent to the location X of the collar 209. In the illustratedembodiment, the opening 220 is immediately proximal the location X,although it is understood that the cam 206 can be reversed such that thecollar 209 and location X are immediately proximal the opening 220.

Best seen in FIG. 23, a helical channel or track 232 is formed in theouter surface of the cylindrical body 207 of the cam 206, extendingbetween the collar 209 and a proximal end of the cylindrical body.Riding in the track is a finger 241 of a follower 240 situated generallybetween the cam and the gear, whose movement is guided by an axial slot242 formed in the gear 204 as the gear is rotated by the knob 202. Adistal end of the contraction wire 35 is anchored to the finger 241 sothat the follower draws the contraction wire 35 longitudinally relativeto the catheter body 12. As a user rotates the knob 202, the gear 204rotates along with its axial slot 242 and the follower 240 therein, eachorbiting the longitudinal axis of the control handle 16. As the follower240 orbits, it slides in the helical channel 232 as guided by the axialslot 242 to move distally or proximally relative to the control handle16. As the follower 240 slides distally, the contraction wire 35 isdrawn distally. As the follower 240 slides proximally, the contractionwire is pushed proximally. Such is a means by which rotational movementof the outer control knob 202 is converted to a longitudinal movement ofthe contraction puller member 35. Advantageously, the distance thefollower 240 can travel along the helical track 232 is not limited toand in fact can be much greater than the length of the cylindrical body207, for greater range or degree of motion in the catheter componentcontrolled by the contraction wire 35. Indeed, the distance the follower240 can travel (and hence amount by which the contraction wire 35 can bemoved) along the cylindrical body 207 depends on the pitch of thehelical track 232 (e.g., width of one complete helix turn) and thediameter of the cylindrical body 207. Accordingly, the control knob 202is designed for rotation of at least 360, if not greater.

The collar 209 of the cam 206 has a radial notch 244 through which thecontraction wire 35 passes to reach the body 207. A lip 249 is formed atthe proximal end of the body 207 of the cam 206 as a snap-fit feature toretain the gear 204 on the body 207. Axial notches 246 allow deflectionof the proximal end of the cam 207 to facilitate the snap-fit feature.Lead wires and other components (e.g., thermocouple wires, cables,irrigation tubing) extending through the protective tubing 152 can passthrough passage 270 between the gear 204 and the knob 202.

In an alternate embodiment, a rotational control assembly 200′ isillustrated in FIG. 27. Selected components are identical or similar;however, differences include a gearless outer rotational control knob202′, a larger, comparably-sized gearless inner rotational member 204′that is generally cylindrical, and a larger, comparably-sized cam 206′,the latter two of which allow all three components to share a commonlongitudinal axis.

In the illustrated embodiment, the outer rotational control knob or ring202′ is mounted on the proximal portion 116 of the control handle 16′.The knob formed of two halves 202′a, 202′b is received in the outercircumferential recess 208 (FIG. 31) formed in the outer surface of thecontrol handle housing halves 16 a′, 16 b′. The knob 202′ is generallycylindrical, for example, in the shape of a ring, with an inner diameterD3 that is slightly greater the recess 208 so that the knob can berotated within the recess 208. There can be circumferential contactbetween the knob 202′ and the handle 16′ so long as the knob can berotated relative to the handle 16′ about the longitudinal axis of thecontrol handle. Likewise, an outer surface of the knob hasfriction-inducing formations 210 to facilitate rotation of the knob 202by a user of the catheter. A portion of the knob may have a diameter D4that is greater than the outer diameter D2 of the handle. However, theinner surface of the knob 202′ is generally smooth.

In this embodiment, the cam 206′ has a similar structure and function tothe cam 206 of the foregoing embodiment with differences that include alarger outer diameter D8 of the cylindrical body 207′ so that it cansupport the inner cylinder 204′ in a generally on-axis or concentricposition within the control handle and the outer knob 202′ and allow thecylinder 204′ and the outer knob 202′ to have a common rotational axis.The collar 209′ of the cam is fixed within a circumferential recess 260formed in the inner surface of the control handle housing halves 16 a′,16 b′.

For rotationally coupling the outer knob 202′ and the inner rotationalmember 204′, for example, for engaging and imparting rotational movementfrom the knob 202′ to the inner rotational cylinder 204′, the innersurface of the outer knob 202′ and outer surface of the inner cylinder204′ have formations, e.g., fingers 250 formed in one that reach intomatching indentations or holes 252 formed in the other. In theillustrated embodiment, there are at least two diametrically opposingfingers 250 formed in the inner surface of the outer knob 202′ thatengage with two diametrically opposing indents 252 formed in the outersurface of the inner rotational cylinder 204′. Thus, as illustrated, theinner cylinder 204′ can have an outer diameter D7 that is slightlysmaller than the inner diameter D1 of the proximal portion 116 of thecontrol handle.

The engagement between the fingers 250 and the holes 252 occurs througha pair of diametrically opposing radial slots 254 formed in the handlehousing halves 16 a, 16 b (FIG. 31). The slots 254 extend transverselyto the longitudinal axis of the control handle. Where the handle has acircumference C, the length of the each of the two slots can be up toabout 0.45 C, as the joining of the two slots would result in adiscontinuity in the proximal portion 116 of the housing halves. Assuch, the outer knob 202′ can be rotated up to about 290 degrees in theclockwise direction or in the counterclockwise direction. While it maybe desirable to avoid a full circular slot, it is understood that thecontrol handle can be constructed with a full circular slot yet have theproximal portion 116 remain connected to the mid and distal portions 112and 114, for example, by internal structural connections therebetween.The angle of rotation achievable by this embodiment is dependent uponthe plurality of fingers and the total material required to maintainadequate rigidity between the distal and proximal ends of the controlhandle 16.

As a user rotates the knob 202′, the fingers 250 rotate the innercylinder 204′ which in turn rotates the axial slot 242 guiding thefollower 240 to orbit about the cam 206′. The follower 240 in turnslides in the helical track 232 moving distally or proximally relativeto the control handle. As the follower 240 slides distally, thecontraction wire 35 is drawn distally, for example, to contract themapping assembly 17. As the follower 240 slides proximally, thecontraction wire 35 is pushed proximally, for example, to expand themapping assembly 17.

It is understood that relative sizing of the components of therotational control assembly is not limited to the illustratedembodiments. In the embodiment of FIGS. 22-25, the outer diameter of thegear 204 can range between about 0.2-0.9 of the inner diameter of theknob 202 so long as there is sufficient engagement in the teeththerebetween. In the embodiment of FIGS. 26-29, the outer diameter ofthe cylinder 204′ can range between 0.2-0.9 of the inner diameter theknob 202′ so long as the fingers are long enough to reach between thecylinder and the knob. For either embodiment, a suitable length L of thehelical track about the cam body can be L=Pi*(D_(E)−D_(C)) where D_(E)is the expanded diameter of the generally circular main portion 39 ofthe mapping assembly 17 and D_(C) is the contracted diameter of thegenerally circular main portion 39.

It is understood that the rotational control assembly uses a barrel-typecam to transform rotational movement of a control knob into usefullinear deflection. The assembly components advantageously utilizeminimal space to achieve desirable linear motions.

In use, a suitable guiding sheath is inserted into the patient with itsdistal end positioned at a desired mapping location. An example of asuitable guiding sheath for use in connection with the present inventionis the Preface™ Braiding Guiding Sheath, commercially available fromBiosense Webster, Inc. (Irvine, Calif.). The distal end of the sheath isguided into one of the chamber, for example, the atria. A catheter inaccordance with the present invention is fed through the guiding sheathuntil its distal end extends out of the distal end of the guidingsheath. As the catheter is fed through the guiding sheath, the mappingassembly 17 is straightened to fit through the sheath. Once the distalend of the catheter is positioned at the desired mapping location, theguiding sheath is pulled proximally, allowing the deflectableintermediate section 14 and mapping assembly 17 to extend outside thesheath, and the mapping assembly 17 returns to its original shape due tothe shape-memory of the support member 54.

By manipulating and rotating the deflection arm 75 of the deflectioncontrol assembly 74 to deflect the intermediate section 14, the mappingassembly 17 is then inserted into a pulmonary vein or other tubularregion (such as the superior vena cava, or inferior vena cava) so thatthe outer circumference of the generally circular main region 39 of theassembly 17 is in contact with a circumference inside the tubularregion. Turning the deflection arm 75 in one direction deflects theintermediate section 14 to that direction. Turning the deflection 75 inthe opposite direction deflects the intermediate section 14 to thatopposite direction. Tension of the deflection 75 is adjusted bymanipulating and rotating the dial 101. Turning the dial 101 in onedirection increases the tension. Turning the dial 101 in the oppositiondirection decreases the tension. Preferably at least about 50%, morepreferably at least about 70%, and still more preferably at least about80% of the circumference of the generally circular main region is incontact with a circumference inside the tubular region.

The circular arrangement of the electrodes 26 permits measurement of theelectrical activity at that circumference of the tubular structure sothat ectopic beats between the electrodes can be identified. The size ofthe generally circular main region 39 permits measurement of electricalactivity along a diameter of a pulmonary vein or other tubular structureof or near the heart because the circular main region has a diametergenerally corresponding to that of a pulmonary vein or the coronarysinus. By manipulating and rotating the outer control knob 202, 202′ ofthe rotational assembly 200, the assembly 17, in particular, thegenerally circular main region 39, is contracted to fit the pulmonaryvein or other tubular structure. By turning the knob in one direction,the contraction wire is drawn proximally to tighten and decrease thediameter of the generally circular region 39. By turning the knob in theopposition direction, the contraction wire is pushed distally to releasethe generally circular region 39 and expands its diameter.

The preceding description has been presented with reference to presentlypreferred embodiments of the invention. Workers skilled in the art andtechnology to which this invention pertains will appreciate thatalterations and changes in the described structure may be practicedwithout meaningfully departing from the principal, spirit and scope ofthis invention. As understood by one of ordinary skill in the art, thedrawings are not necessarily to scale. Accordingly, the foregoingdescription should not be read as pertaining only to the precisestructures described and illustrated in the accompanying drawings, butrather should be read consistent with and as support to the followingclaims which are to have their fullest and fair scope.

What is claimed is:
 1. A catheter comprising: a catheter body; adeflectable intermediate section distal the catheter body; a mappingassembly distal the intermediate section, the mapping assembly having agenerally circular portion; a control handle proximal the catheter body,the control handle having: a deflection control assembly; and arotational control assembly having an outer rotational member, an innerrotational member and a cam, the inner rotational member being rotatablymounted on at least a portion of the cam, the cam being fixed to thecontrol handle housing and having a helical track with a track lengththat is greater than a length of the cam, the outer rotational memberbeing in rotational engagement with the inner rotational member; firstand second puller members responsive to the deflection control assemblyconfigured to deflect the intermediate section; and a third pullermember responsive to the rotational control assembly configured tocontract the generally circular portion of the mapping assembly.
 2. Thecatheter of claim 1, wherein a proximal end of the third puller memberis anchored in the rotational control assembly, such that rotation ofthe outer rotational member by a user moves the third puller memberlongitudinally relative to the catheter body.
 3. The catheter of claim1, wherein the rotational control assembly further comprises a followerto which a proximal end of the third puller member is anchored, thefollower being configured to follow the movement of the inner rotationalmember so as to slide in the helical track on the cam.
 4. The catheterof claim 3, wherein rotation of the outer rotational member results inmovement of the follower within the helical track on the cam, and theouter rotational member is configured for rotation of at least 360°. 5.The catheter of claim 1, wherein the outer rotational member comprisesfirst and second halves that are configured for snap-fit engagement. 6.The catheter of claim 1, wherein the outer rotational member comprisesfirst and second halves that are joined together by glue or sonicwelding.
 7. The catheter of claim 1, wherein the inner rotational memberand the outer rotational member have a common rotational axis.
 8. Thecatheter of claim 1, wherein the outer rotational member has a firstrotational axis and the inner rotational member has a second rotationalaxis different from the first rotational axis.
 9. The catheter of claim8, wherein the first rotational axis is on axis with a longitudinal axisof the control handle.
 10. The catheter of claim 1, wherein therotational control assembly is proximal of the deflection controlassembly.
 11. The catheter of claim 1, wherein the rotational controlassembly is distal of the deflection control assembly.
 12. The catheterof claim 1, wherein the control handle further comprises a handlehousing, and the outer rotational member is received in an outercircumferential recess in an outer surface of the handle housing. 13.The catheter of claim 12, wherein the outer rotational member has aninner diameter that is greater than an outer diameter of the outercircumferential recess.
 14. A multifunctional catheter control handle,comprising: a deflection control assembly having a deflection arm and arocker member; and a rotational control assembly having an outerrotational member, an inner rotational member and a cam, the innerrotational member being rotatably mounted on at least a portion of thecam, the cam being fixed to the control handle housing and having ahelical track with a track length that is greater than a length of thecam, the outer rotational member and the inner rotational member beingrotationally coupled by at least one finger on one of the outerrotational member and the inner rotational member that engages at leastone indentation or opening in the other of the outer rotational memberand the inner rotational member when the outer rotational member isrotated; first and second puller members, each with a proximal endanchored to the deflection control assembly; and a third puller memberwith a proximal end anchored to the rotational control assembly.
 15. Thecontrol handle of claim 14, wherein the rotational control assemblyfurther includes a follower to which the proximal end of the thirdpuller member is anchored, the follower being configured to follow themovement of the inner rotational member so as to slide in the helicaltrack on the cam.
 16. The control handle of claim 15, wherein rotationof the outer rotational member results in movement of the followerwithin the helical track on the cam, and the outer rotational member isconfigured for rotation of at least 360°.
 17. The control handle ofclaim 14, wherein the outer rotational member comprises first and secondhalves that are configured for snap-fit engagement.
 18. The catheter ofclaim 1, wherein the outer rotational member comprises first and secondhalves that are joined together by glue or sonic welding.
 19. Thecatheter of claim 1, wherein the rotational control assembly is distalof the deflection control assembly.
 20. The catheter of claim 1, whereinthe control handle further comprises a handle housing, and the outerrotational member is received in an outer circumferential recess in anouter surface of the handle housing.